A companion spec define a VariableNode as following (OPC UA for IO-Link)
The Variable ProcessDataOutput shall be mapped to the cyclically data transferred to the device. It is vendor-specific, if the Variable is writeable.
The related NodeSet2-XML defines this VariableNode with attribute AccessLevel CurrentRead/CurrentWrite.
So below ObjectTypes the AccessLevel is defined for this VariableNode.
But whats about the Instance space if there will never a support to write the VariableNode.
Is it allowed to change the attribute AccessLevel to CurrentRead in the instance space?
Or must the each time CurrentRead|CurrentWrite and only the UserAccessLevel will be CurrentRead?
This question also relevant for the Method attributes Executeable and UserExecutable.
thx & br
In general, any permission related attributes have rules defined by the modeller. In this case, the modeller made it clear that write access is optional so you can change the AccessLevel to RO.
In other cases, you would keep the same AccessLevel but you could do whatever you need with UserAccessLevel.